Hadith #17 (The Forty Hadith of Imam Nawawi)
Book: Allah has prescribed excellence (ihsan) in all things
Narrator(s): Abu Ya'la Shaddad ibn Aws
Grade: Sahih

Verily Allah has prescribed ihsan (proficiency, perfection) in all things. So if you kill then kill well; and if you slaughter, then slaughter well. Let each one of you sharpen his blade and let him spare suffering to the animal he slaughters.

Source: https://parallelquran.com/hadith/forty-nawawi-17/